Actuator of regulator and fluid regulator

ABSTRACT

An actuator of a regulator is provided. The actuator is connected to one end of a valve rod ( 212/312 ). The actuator comprises a shell ( 203/303 ); a limiting component ( 205/305 ), the limiting component ( 205/305 ) being disposed on an inner wall of the shell ( 203/303 ); a diaphragm assembly ( 204/304 ), the diaphragm assembly ( 204/304 ) being accommodated in the shell ( 203/303 ), and the diaphragm assembly ( 204/304 ) being movably sleeved on the valve rod ( 212/312 ); and an elastic element ( 226/326 ), the elastic element ( 226/326 ) being accommodated in the shell ( 203/303 ), and the elastic element ( 226/326 ) being coupled to the diaphragm assembly ( 204/304 ), and being movably sleeved, between the diaphragm assembly ( 204/304 ) and a tip of one end of the valve rod ( 212/312 ), on the valve rod ( 212/312 ) in a compressed mode. An inner diameter of a portion, making contact with the shell ( 203/303 ), of the limiting component ( 205/305 ) is smaller than an outer diameter of an upper portion of the diaphragm assembly ( 204/304 ), and the limiting component ( 205/305 ) is located above the diaphragm assembly ( 204/304 ). A fluid regulator having the actuator is provided. By means of the actuator, the technical problem that a valve rod, a valve flap and a valve port are deformed and even damaged due to extremely large stress in the regulator is solved, the valve rod, the valve flap and the valve port of a valve element assembly are buffered to a certain extent when bearing extremely large stress, and therefore damage is avoided.

TECHNICAL FIELD

The present invention relates to the field of fluid control, and in particular, to an actuator of a regulator and a fluid regulator.

RELATED ART

The pressure of fluid supplied by a universal fluid distribution system may vary with a system requirement, climate, a supply source, and/or other factors, and in order to meet the transportation requirement of most terminal devices requiring the fluid to be in line with a predetermined pressure and at or lower than the maximum capacity of a fluid regulator, the fluid regulator is implemented in these distribution systems to ensure that the requirement of the terminal devices is met.

FIG. 1 shows a conventional fluid regulator 100. The fluid regulator 100 usually includes an actuator 12 and a regulator valve 14.

The regulator valve 14 has a fluid inlet 30 for receiving fluid from, for example, a fluid distribution system and a fluid outlet 34 for transporting the fluid to a terminal device. The regulator valve 14 includes a valve port 28 disposed between the fluid inlet 30 and the fluid outlet 34. The transportation of the fluid from the fluid inlet 30 to the fluid outlet 34 has to be conducted through the valve port 28. The regulator valve 14 further includes a valve rod 26 and a valve flap 32. The valve flap 32 is disposed at an end portion of one end, which is located in the regulator valve 14, of the valve rod 26, and the valve flap 32 and the valve rod 26 can be connected into a whole. The valve flap 32 is adapted to move between a closed position of engaging with the valve port 28 and an open position of leaving the valve port 28, and the valve rod 26 is used for driving the valve flap 32 to move between the closed position and the open position.

The actuator 12 is coupled to the regulator valve 14 to ensure that the pressure at the fluid outlet 34 of the regulator valve 14, that is, the outlet pressure, meets a desired outlet pressure. The actuator 12 and the regulator valve 14 are in communication with each other and fluid is allowed to flow through. The actuator 12 includes a control spring 22, a shell 24, a diaphragm 18, an upper tray 16, and a lower tray 20. The shell 24 and the diaphragm 18 define a hole cavity that is in communication with the fluid outlet 34 of the regulator 14 and can allow the fluid to flow through, and the diaphragm 18 is used for sensing the outlet pressure of the regulator valve 14. The control spring 22 is disposed in the shell 24, and engages with the upper tray 16 at the top of the diaphragm 18. Therefore, the desired outlet pressure is set based on the control spring 22. The diaphragm 18 is further coupled to the valve rod 26 of the regulator 14, and the upper tray 16, the diaphragm 18, and the lower tray 20 are connected into a whole through the valve rod 26 and a valve rod nut 36. The diaphragm 18 drives the valve rod 26 to move based on the sensed pressure, and the valve rod 26 drives the valve flap 32 to move together, so as to control opening and closing of the regulator valve 14, thereby achieving the function of adjusting the pressure of the fluid outlet 34.

When the regulator works normally, the pressure of the fluid outlet 34 rises over the desired pressure of the outlet, the diaphragm 18 senses a relatively large pressure so as to drive the valve rod 26 of the regulator to move, thus driving the valve flap 32 to reach the closed position of the valve port 28 to seal the valve port. The regulator is closed to prevent the pressure of the fluid outlet from rising.

With increase of the working time of the regulator, a sealing effect between the valve flap 32 and the valve port 28 may be reduced, leakage may occur when the regulator is closed, and at this point, the pressure of the fluid outlet 34 may rise all the time, and may even be equal to the inlet pressure, or the pressure of the fluid outlet 34 fluctuates in a too large range, for example, a water hammer phenomenon, resulting in that the pressure of the fluid outlet 34 suddenly rises. At this point, as the force, which is generated by the pressure of the fluid outlet 34, acting on the diaphragm 18 may be completely transferred to the valve rod 26, the valve flap 32, and the valve port 28 of the valve element assembly, extremely large stress may result in that the valve rod, the valve flap, and the valve port are deformed or even damaged to be dangerous.

Therefore, with respect to the above problems, an actuator of a regulator and a fluid regulator are provided, to prevent that the valve element assembly is deformed and damaged due to extremely large stress.

SUMMARY

In one aspect of the present invention, an actuator of a regulator is provided, the actuator being connected to one end of a valve rod, wherein the actuator includes: a shell; a limiting component, the limiting component being disposed on an inner wall of the shell; a diaphragm assembly, the diaphragm assembly being accommodated in the shell, and the diaphragm assembly being movably sleeved on the valve rod; and an elastic element, the elastic element being accommodated in the shell, and the elastic element being coupled to the diaphragm assembly, and being movably sleeved, between the diaphragm assembly and the tip of one end of the valve rod, on the valve rod in a compressed mode; wherein an inner diameter of a portion, making contact with the shell, of the limiting component is smaller than an outer diameter of an upper portion of the diaphragm assembly, and the limiting component is located above the diaphragm assembly.

The limiting component is a protruding portion or a reinforcing rib.

The diaphragm assembly includes a diaphragm, an upper tray and a lower tray fixed to upper and lower sides of the diaphragm respectively, and the upper portion of the diaphragm assembly is the upper tray.

A sectional view of the lower tray is in an inverted T-shape, a central through hole is disposed on the lower tray, the diaphragm and the upper tray are fixedly sleeved on an outer side of the central through hole, and the diaphragm assembly is movably sleeved on an outer side of one end of the valve rod via the central through hole.

A boss is disposed on the valve rod, an upper portion of the boss is located in the shell and on a lower side of the diaphragm assembly, and the lower tray is in contact with the boss.

A groove that accommodates the boss is disposed on the lower tray.

The actuator further includes: a sealing element, the sealing element being disposed between the valve rod and the diaphragm assembly, and the sealing element being accommodated in a groove disposed on the valve rod or accommodated in the groove disposed on the lower tray.

The sealing element is a rubber component or an elastic component made of metal.

The elastic element is a spring or a component made of rubber.

In another aspect of the present invention, a fluid regulator is provided, including the actuator described in the above.

The fluid regulator further includes: a valve, the valve being coupled to the actuator; wherein the valve includes: a valve body; a fluid channel passing through the valve body and having an inlet and an outlet; a valve rod; a valve port defined in the fluid channel; and a valve flap disposed in the valve body.

Through the actuator of the regulator and the fluid regulator provided in the present invention, an elastic element is movably sleeved on one end of the valve rod, and the elastic element is coupled to a diaphragm assembly, which, in combination with a limiting structure between the upper portion of the diaphragm assembly (accommodated in the shell) and the limiting component (located on an inner wall of the shell and located above the diaphragm assembly) (an inner diameter of a portion, making contact with the shell, of the limiting component is smaller than an outer diameter of an upper portion of the diaphragm assembly), when the fluid outlet generates an overlarge stress, enables the valve rod to be subject to a downward buffering force through the elastic element while the valve rod is subject to upward stress, that is, the valve rod buffers the upward stress to a certain extent. In addition, because the valve element assembly is an entirety consisting of a valve rod, a valve flap, and a valve port, when the valve rod buffers the stress to a certain extent, the stress to the valve flap and the valve port is also reduced. Thus, through the actuator of the regulator and the fluid regulator with the above structure, the problem that the valve rod, the valve flap, and the valve port of the valve element assembly are deformed and even damaged due to extremely large stress at the fluid outlet is solved, thus achieving the technical effect of protecting the valve element assembly when the stress at the fluid outlet is extremely large.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of embodiments of the present invention will be easier to be understood through the following description about the accompanying drawings, wherein:

FIG. 1 is a side sectional view of a conventional fluid regulator;

FIG. 2 is a side sectional view of an actuator of a regulator according to an embodiment disclosed in the present invention;

FIG. 3 is a side sectional view of a fluid regulator according to an embodiment disclosed in the present invention;

FIG. 4 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention;

FIG. 5 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention;

FIG. 6 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention;

FIG. 7 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention;

FIG. 8 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention; and

FIG. 9 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention.

DETAILED DESCRIPTION

The following descriptions about preferred embodiments are merely exemplary, but are by no means limitations to the present invention and applications or use thereof. Identical reference numerals are used in respective accompanying drawings to represent identical components, and thus the structures of identical components are not repeated.

The technical solution of the present invention is further described below with reference to the accompanying drawings and specific embodiments.

FIG. 2 is a side sectional view of an actuator of a regulator according to an embodiment disclosed in the present invention. The actuator 200 includes a shell 203, a limiting component 205 located on an inner wall of the shell 203, and a diaphragm assembly 204 accommodated in the shell 203. The limiting component 205 is located above the diaphragm assembly 204, and the actuator is connected to one end of a valve rod of the regulator.

The shell 203 includes a spring sleeve 210 and a lower membrane cover 211.

The limiting component 205 is located on the inner wall of the shell 203, and located above the diaphragm assembly 204 (in the direction as shown in FIG. 2). As a preferred embodiment, the limiting component 205 is located on an inner wall of the spring sleeve 210.

Preferably, the limiting component 205 may be a protruding portion located on the inner wall of the shell 203, or a reinforcing rib. The protruding portion may be a protruding portion formed by changing the size of the inner diameter of the shell 203, as the limiting component 205 shown in FIG. 2; the protruding portion may also be a protruding portion located on the inner wall of the shell 203 and extending from the inner wall of the shell 203 to the direction of the axis of the shell 203, as the limiting component 705 shown in FIG. 7 (FIG. 7 is a side sectional view of a fluid regulator according to an embodiment); the reinforcing rib may be a component located on the inner wall of the shell and extending downwards along a sidewall of the shell (in the direction as shown in FIG. 8 and FIG. 9), which may be columnar, strip-like, or ribbed, or the reinforcing rib may also be a component extending downwards from the top of the inner wall of the shell (in the direction as shown in FIG. 8 and FIG. 9), which may be columnar, strip-like, or ribbed, wherein FIG. 8 and FIG. 9 show two preferred limiting structures, and FIG. 8 and FIG. 9 are sectional views of an embodiment of a reinforcing rib (FIG. 8 illustrates a limiting structure 805 having six reinforcing ribs, and FIG. 9 illustrates a limiting structure 905 having eight reinforcing ribs). During the implementation, those skilled in the art may set the protruding portion or reinforcing rib according to actual needs.

The diaphragm assembly 204 is located in the shell 203, and the diaphragm assembly 204 includes a diaphragm 218, an upper tray 216, and a lower tray 220. The diaphragm 218 is fixedly mounted in the shell 203, and the upper tray 216 and the lower tray 220 are fixedly connected to upper and lower sides of the diaphragm 218 respectively, to form a sub-assembly, that is, the diaphragm assembly 204 is integrally connected.

The limiting component 205 and the diaphragm assembly 204 (in the direction as shown in FIG. 2) have a gap in the vertical direction, allowing the diaphragm assembly to move upwards within a range (in the direction as shown in FIG. 2), that is, move towards a direction close to the limiting component 205. The inner diameter of the portion, making contact with the shell 203, of the limiting component 205 is smaller than the outer diameter of the upper portion of the diaphragm assembly, and the upper portion of the diaphragm assembly 204 may be the upper tray 216.

The diaphragm assembly 204 is movably sleeved on one end of the valve rod 212 cooperating with the actuator, and the diaphragm assembly 204 and the valve rod 212 may move relatively. A boss 214 is disposed on the valve rod 212, and an upper portion of the boss 214 is located in the shell 203 and on a lower side of the diaphragm assembly 204, that is, in the direction as shown in FIG. 2, the upper portion of the boss 214 may be located in a cavity defined by the diaphragm 218 and the lower membrane cover 211, and the boss 214 may be a boss coaxial with the valve rod 212, and may also be a boss not coaxial with the valve rod. Moreover, the diaphragm assembly 204 is in contact with the boss 214 on the valve rod 212. Specifically, the lower tray 220 of the diaphragm assembly 204 is in contact with the boss 214 on the valve rod 212.

The actuator 200 further includes an elastic element 226 disposed in the shell 203. The elastic element 226 is accommodated in the shell 203. The elastic element 226 is coupled to the diaphragm assembly 204, and is disposed between the diaphragm assembly 204 and the tip of one end of the valve rod 212. The tip of one end of the valve rod 212 may be a valve rod nut 213, and the elastic element 226 is movably sleeved on the valve rod in a compressed mode. In an initial state, the elastic element 226 is configured to be in a compressed state. Moreover, the elastic force of the elastic element 226 should meet a closing force required by a product, that is, the elastic force of the elastic element 226 should ensure that the valve port (not shown in FIG. 2, the valve port is opened or closed by driving, by the valve rod 212, a valve flap connected to the valve rod 212) can be closed normally.

Specifically, the elastic element 226 is, in a compressed mode, movably sleeved on one end of the valve rod 212 cooperating with the diaphragm assembly 204. An upper end of the elastic element 226 may abut against the valve rod nut 213, and a lower end of the elastic element 226 is coupled to an upper side of the diaphragm assembly 204. During the implementation, the elastic element 226 may be a spring or a component made of rubber, and preferably, may be a universal helical spring, a belleville spring, a conical spring or a component made of rubber shown in FIG. 2.

A sealing element 222 is disposed between the valve rod 212 and the diaphragm assembly 204. A groove that accommodates the sealing element 222 is disposed on the valve rod 212 or on the lower tray 220. The groove may be ring-like. The valve rod 212 and the diaphragm assembly 204 may be dynamic sealing structures. The sealing element 222, preferably, may be a rubber component (for example, an O ring) or an elastic component made of metal, and preferably may be a metal C ring, or may be a metal O ring.

Preferably, a sectional view of the lower tray 220 may be in an inverted T-shape. A central through hole 221 is disposed on the lower tray 220, the diaphragm 218 and the upper tray 216 are fixedly sleeved on an outer side of the central through hole 221 of the lower tray 220, the diaphragm assembly 204 is movably sleeved on an outer side of one end of the valve rod 212 via the central through hole 221 of the lower tray 220, and the diaphragm assembly 204 may fasten, through a nut, the diaphragm 218 and the upper tray 216 that are sleeved on the lower tray 220 to the lower tray 220, thereby achieving the aim of fixed connection.

Preferably, a groove that accommodates the boss 214 is disposed on the lower tray 220.

During operation of the actuator 200, the diaphragm assembly 204 may move relative to the shell 203. When the diaphragm 218 is subject to an upward pressure in the direction shown in FIG. 2, the diaphragm assembly 204 moves upwards with the direction shown in FIG. 2, and at the same time, compresses the elastic element 226, that is, the elastic element 226 is continuously compressed from an initial state, till the upper tray 216 makes contact with the limiting component 205 on the inner wall of the shell 203. As the inner diameter of the portion, making contact with the shell 203, of the limiting component 205 is smaller than the outer diameter of the upper portion of the diaphragm assembly 205, that is, smaller than the outer diameter of the upper tray 216, and the limiting component 205 is located above the diaphragm assembly 204, achieving the function of limiting.

During operation of the actuator 200, when the diaphragm 218 senses that the upward pressure shown in FIG. 2 exceeds an allowable pressure, the pressure acts on the diaphragm assembly 204. The diaphragm assembly 204, that is, the upper tray 216, the diaphragm 218, and the upper tray 220, moves upwards relative to the valve rod 212 and the shell 203 (in the direction as shown in FIG. 2) in the direction shown in FIG. 2, and at the same time, the elastic element 226 is compressed, till the upper tray 216 of the diaphragm assembly 204 makes contact with the limiting component 205 on the inner wall of the shell 203, and at this point, the valve element assembly is limited, that is, the valve rod 212, the valve flap, and the valve port (not shown in FIG. 2) are limited, to form a limiting structure. In this process, as there is relative movement between the valve rod 212 and the diaphragm assembly 204, a gap may be generated between the boss 214 of the valve rod 212 and the lower tray 220. As the sealing element 222 is disposed between the valve rod 212 and the diaphragm assembly 204, and the sealing element 222 is disposed in a ring-like groove on the valve rod 212 or the lower tray 220, leakage may not occur. Due to the limiting structure between the diaphragm assembly 204 and the shell 203, an extremely large force may act on the limiting component 205 on the inner wall of the shell 203 via the diaphragm assembly 204 and the upper tray 216. Between the valve rod 212 and the diaphragm assembly 204, there is a dynamic sealing structure, the valve element assembly, i.e., the valve rod 210, the valve flap, and the valve port (not shown in FIG. 2), is only subject to the force generated when the elastic element 226 is compressed, so that the force applied to the valve element assembly is buffered, thus protecting that the valve rod 212, the valve flap, and the valve port (not shown in FIG. 2) of the valve element assembly may not be damaged due to extremely large force.

The actuator further includes a biasing component 224 disposed in the shell 203, coupled to the diaphragm assembly 204, and configured to apply a biasing force to the valve rod 212 via the diaphragm assembly 204. Specifically, the biasing component 224 may be a spring, an upper end thereof is fixed onto the spring sleeve 210 of the shell 203, and a lower end thereof is coupled to an upper side of the diaphragm assembly 204.

FIG. 3 is a side sectional view of a fluid regulator according to an embodiment of the present invention, that is, a fluid regulator including the actuator described in the above embodiment. The fluid regulator 300 may include an actuator 301 and a valve 302.

In this embodiment, the valve 302 includes a valve body 328, a valve element assembly 306, and a fluid channel defined by a fluid inlet 330 and a fluid outlet 332 on the valve body 328. The fluid channel is defined as passing through the valve body 328. The valve element assembly 306 includes a valve rod 312, a valve port 334, and a valve flap 336. The valve port 334 is defined between the fluid inlet 330 and the fluid outlet 332 of the fluid channel, and the fluid needs to be transported between the fluid inlet 330 and the fluid outlet 332 through the valve port 334. The valve flap 336 is disposed in the fluid channel and connected to the valve rod 312, and the valve rod 312 is used for driving the valve flap 336 to move between a closed position of engaging with the valve port 334 and an open position of leaving the valve port 334.

The actuator 301 is coupled to the valve 302.

The actuator 301 includes a shell 303, a diaphragm assembly 304 accommodated in the shell 303, and a limiting component 305 located on an inner wall of the shell 303.

The shell 303 includes a spring sleeve 310 and a lower membrane cover 311.

The limiting component 305 is located on the inner wall of the shell 303, and located above the diaphragm assembly 304 (in the direction as shown in FIG. 3). As a preferred embodiment, the limiting component 305 is located on an inner wall of the spring sleeve 310.

Preferably, the limiting component 305 may be a protruding portion located on the inner wall of the shell 303, and may also be a reinforcing rib. The protruding portion may be a protruding portion formed by changing the size of the inner diameter of the shell 303, as the limiting component 305 shown in FIG. 3; the protruding portion may also be a protruding portion located on the inner wall of the shell 303 and extending from the inner wall of the shell 303 to the direction of the axis of the shell 303, as the limiting component 705 shown in FIG. 7 (FIG. 7 is a side sectional view of a fluid regulator according to an embodiment); the reinforcing rib may be a component located on the inner wall of the shell 303 and extending downwards along a sidewall of the shell (in the direction as shown in FIG. 8 and FIG. 9), which may be columnar, strip-like, or ribbed, or the reinforcing rib may also be a component extending downwards from the top of the inner wall of the shell (in the direction as shown in FIG. 8 and FIG. 9), which may be columnar, strip-like, or ribbed. During the implementation, those skilled in the art may set the protruding portion or reinforcing rib according to actual needs.

The diaphragm assembly 304 is located in the shell 303, and the diaphragm assembly 304 includes a diaphragm 318, an upper tray 316, and a lower tray 320. The diaphragm 318 is fixedly mounted in the shell 303, and the upper tray 316 and the lower tray 320 are fixedly connected to upper and lower sides of the diaphragm 318 respectively, to form a sub-assembly, that is, the diaphragm assembly is integrally connected.

The limiting component 305 and the diaphragm assembly 304 (in the direction as shown in FIG. 3) have a gap in the vertical direction, allowing the diaphragm assembly to move upwards within a range (in the direction as shown in FIG. 3), that is, move towards a direction close to the limiting component 305. The inner diameter of the portion, making contact with the shell 303, of the limiting component 305 is smaller than the outer diameter of the upper portion of the diaphragm assembly 304, and the upper portion of the diaphragm assembly 304 may be the upper tray 316.

The diaphragm assembly 304 is movably sleeved on the valve rod 312, and the diaphragm assembly 304 and the valve rod 312 may move relatively. A boss 314 is disposed on the valve rod 312, and an upper portion of the boss 314 is located in the shell 303 and on a lower side of the diaphragm assembly 304, that is, in the direction as shown in FIG. 3, the upper portion of the boss 314 may be located in a cavity defined by the diaphragm 318 and the lower membrane cover 311, and the boss 314 may be a boss coaxial with the valve rod 312, and may also be a boss not coaxial with the valve rod. Moreover, the boss 314 is in contact with the lower tray 320 of the diaphragm assembly 304.

During operation of the fluid regulator 300, the diaphragm assembly 304 may move relative to the shell 303. The diaphragm 318 and the lower membrane cover 311 of the shell 303 define a hole cavity 338. The hole cavity 338 is in communication with the fluid outlet 332 and can allow the fluid to flow through, to cause the diaphragm 318 to sense the pressure of the fluid outlet of the valve 302. When the diaphragm 318 senses, through the hole cavity 338, extremely large pressure caused by leakage or a water hammer phenomenon of the valve port 334, that is, the diaphragm 318 is subject to upward pressure, the diaphragm assembly 304 moves upwards, and the diaphragm assembly 304 moves upwards till the upper tray 316 makes contact with the limiting component 305 on the inner wall of the shell 303, to play a role of limiting, that is, the diaphragm assembly 304 and the limiting component 305 form a limiting structure. Specifically, the inner diameter of the portion, making contact with the shell 303, of the limiting component 305 is smaller than the outer diameter of the upper portion of the diaphragm assembly 304. The upper portion of the diaphragm assembly 304 may be the upper tray 316.

An elastic element 326 is accommodated in the shell 303. The elastic element 326 is coupled to the diaphragm assembly 304, and disposed between the diaphragm assembly 304 and the tip of one end of the valve rod 312. The tip of one end of the valve rod 312 may be a valve rod nut 313, and the elastic member 326 is movably sleeved on the valve rod 312 in a compressed mode. Moreover, in an initial state, the elastic element 326 is configured to be in a compressed state. Also, the elastic force of the elastic element 326 should meet a closing force required by a product, that is, the elastic force of the elastic element 326 should ensure that the valve port 334 can be closed normally. Specifically, an upper end of the elastic element 326 may abut against the valve rod nut 313, and a lower end of the elastic element 326 is coupled to an upper side of the diaphragm assembly 304, so that the elastic element is movably sleeved on one end of the valve rod 312 cooperating with the diaphragm assembly 304. That is, the elastic element 326 is movably sleeved on the valve rod 312, and compressed between the valve rod nut 313 and the diaphragm assembly 304. The elastic element 326 may be a spring or a component made of rubber, and preferably, may be a universal helical spring, a belleville spring, a conical spring or a component made of rubber.

A sealing element 322 is disposed between the valve rod 312 and the diaphragm assembly 304. The valve rod 312 and the diaphragm assembly 304 form a dynamic sealing structure. A groove that accommodates the sealing element 322 is disposed on the valve rod 312 or on the lower tray 320. The groove may be ring-like. The sealing element, preferably, may be a rubber component (for example, an O ring) or an elastic component made of metal, and preferably may be a metal C ring, or may be a metal O ring.

Preferably, a sectional view of the lower tray 320 may be in an inverted T-shape and provided thereon with a central through hole 321. The diaphragm 318 and the upper tray 316 are fixedly sleeved on an outer side of the central through hole 321 of the lower tray 320, the diaphragm assembly 304 is movably sleeved on an outer side of one end of the valve rod 312 via the central through hole 321 of the lower tray 320, and the fixed connection of the diaphragm assembly 304 may fasten, through a nut, the diaphragm 318 and the upper tray 316 that are sleeved on the lower tray 320 to the lower tray.

Preferably, a groove that accommodates the boss 314 may be disposed on the lower tray 320.

The actuator further includes a biasing component 324 disposed in the shell 303, coupled to the diaphragm assembly 304, and configured to apply a biasing force to the valve rod 312 via the diaphragm assembly 304. Specifically, the biasing component 324 may be a spring, an upper end thereof is fixed onto the shell 303, and a lower end thereof is coupled to an upper side of the diaphragm assembly 304.

During operation of the fluid regulator 300, when the valve flap 336 is opened, the fluid is transported from the fluid inlet 330, via the valve port 334, to the fluid outlet 332 to be sent out; at this point, the pressure at the fluid outlet 332 rises. When the pressure at the fluid outlet 332 exceeds the desired pressure, the valve flap 336 and the valve port 334 are sealed in a contact mode, to prevent the pressure at the fluid outlet 332 from rising.

However, with the increase of the working time of the fluid regulator 300, a sealing effect between the valve flap 336 and the valve port 334 may be reduced, leakage may occur when the fluid regulator 300 is closed, and at this point, the pressure at the fluid outlet 332 may rise all the time, and may even be equal to the pressure at the fluid inlet 330, or the pressure at the fluid outlet 332 fluctuates in a too large range, for example, a water hammer phenomenon, resulting in that the pressure at the fluid outlet 332 suddenly rises, and the rising pressure acts on the diaphragm 318 via the hole cavity 338. At this point, the diaphragm assembly 304 moves upwards in the direction shown in FIG. 3 relative to the valve rod 312 and the spring sleeve 310 of the shell 303, and at the same time, the elastic element 326 is compressed, that is, the elastic element 326 is continuously compressed from the initial compressed state, till the diaphragm assembly 304 moves upwards in the direction shown in FIG. 3 to the upper tray 316 to make contact with the limiting component 305. The inner diameter of the portion, making contact with the shell 303, of the limiting component 305 is smaller than the outer diameter of the upper portion of the diaphragm assembly 304, and the upper portion (in the direction shown in FIG. 3) of the diaphragm assembly 304 may be the upper tray 316, so that the diaphragm assembly 304 is limited. Preferably, the elastic element 326 may be a spring or a component made of rubber.

In a process that the diaphragm assembly 304 moves upwards relative to the valve rod 312, a gap may be generated between the boss 314 of the valve rod 312 and the lower tray 320. As the sealing element 322 is disposed between the valve rod 312 and the diaphragm assembly 304, and the sealing element 322 is disposed in the ring-like groove on the valve rod, leakage may not occur. Therefore, during operation of the fluid regulator, an extremely large force generated due to sudden rise of the pressure at the fluid outlet 332 may act on the limiting component 305 via the diaphragm assembly 304, and the valve rod 312, the valve flap 336, and the valve port 334 of the valve element assembly 306 are only subject to the force generated by compression on the elastic element 326 in the process, so that the force (stress) applied to the valve element assembly 306 is buffered, thus protecting the valve rod 312, the valve flap 336, and the valve port 334 of the valve element assembly from being damaged due to extremely large force (stress).

FIG. 4 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention, wherein the elastic element 426 in the fluid regulator 400 is a conical spring. FIG. 5 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention, wherein the elastic element 526 in the fluid regulator 500 is a belleville spring. FIG. 6 is a side sectional view of a fluid regulator according to another embodiment disclosed in the present invention, wherein the elastic element 626 in the fluid regulator 600 is an elastic rubber block. It should be noted that other elements of the fluid regulator and operation manners thereof shown in FIG. 4, FIG. 5, and FIG. 6 may employ the elements and operation manners identical with or similar to those of the fluid regulator in the embodiment shown in FIG. 3 for processing, which are not repeated herein.

It should be noted that, herein, the terms “include”, “comprise”, or any variants thereof are intended to cover a non-exclusive inclusion, such that a process, a method, an article, or a device that includes a series of elements not only includes such elements but also includes other elements not specified expressly, or may further include inherent elements of the process, method, article, or device. In the absence of more restrictions, an element limited by “include a/an . . . ” does not exclude other same elements existing in the process, method, article, or device that includes the element.

The above descriptions are merely preferred embodiments of the present invention, but are not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present invention are all included in the protection scope of the present invention. 

1. An actuator of a regulator, the actuator being connected to one end of a valve rod, wherein the actuator comprises: a shell; a limiting component, the limiting component being disposed on an inner wall of the shell; a diaphragm assembly, the diaphragm assembly being accommodated in the shell, and the diaphragm assembly being movably sleeved on the valve rod; and an elastic element, the elastic element being accommodated in the shell, and the elastic element being coupled to the diaphragm assembly, and being movably sleeved, between the diaphragm assembly and a tip of one end of the valve rod, on the valve rod in a compressed mode; wherein an inner diameter of a portion, making contact with the shell, of the limiting component is smaller than an outer diameter of an upper portion of the diaphragm assembly, and the limiting component is located above the diaphragm assembly.
 2. The actuator according to claim 1, wherein the limiting component is a protruding portion or a reinforcing rib.
 3. The actuator according to claim 1 or 2, wherein the diaphragm assembly comprises a diaphragm, an upper tray and a lower tray fixed to upper and lower sides of the diaphragm respectively, and the upper portion of the diaphragm assembly is the upper tray.
 4. The actuator according to claim 3, wherein a sectional view of the lower tray is in an inverted T-shape, a central through hole is disposed on the lower tray, the diaphragm and the upper tray are fixedly sleeved on an outer side of the central through hole, and the diaphragm assembly is movably sleeved on an outer side of one end of the valve rod via the central through hole.
 5. The actuator according to claim 3, wherein a boss is disposed on the valve rod, an upper portion of the boss is located in the shell and on a lower side of the diaphragm assembly, and the lower tray is in contact with the boss.
 6. The actuator according to claim 5, wherein a groove that accommodates the boss is disposed on the lower tray.
 7. The actuator according to claim 1 or 2, wherein the actuator further comprises: a sealing element, the sealing element being disposed between the valve rod and the diaphragm assembly, and the sealing element being accommodated in a groove disposed on the valve rod or accommodated in the groove disposed on the lower tray.
 8. The actuator according to claim 7, wherein the sealing element is a rubber component or an elastic component made of metal.
 9. The actuator according to claim 1 or 2, wherein the elastic element is a spring or a component made of rubber.
 10. A fluid regulator, comprising the actuator according to any of claims 1 to
 9. 